Try flooding them out by putting your hose on the strongest spray possible.
Pay someone to clean out underneath your porch.
Use a push broom to clear it out yourself, this may involve laying on the ground in a snake's path. (This is where having children is beneficial).
Depending upon the structure of your porch see is there is something you can administer between the boards of your porch.
Once you do get the snakes out, or think they have left, seal it up, either with wood or heavy gauge screening.
Course, I hate to further worry you, but their prolonged presence means that there must be a good food source near by. Most snakes feed on vermin like mice and rats. That could mean even more trouble than 2 unidentified snakes.
Last edited by Wendy Tall One; 09/05/08 10:39 PM.